1. Field of the Invention
The invention relates to a client/server system in which a client terminal connected with a server through a transmission path of a limited bandwidth plays a multimedia program which is stored in the server and is comprised of multimedia objects such as moving pictures, still pictures, sounds and texts while reading the objects in real time from the server.
2. Description of the Prior Art
In such a system, a user of a client terminal is permitted to select one of a plurality of programs and to enter commands such as a play, a stop, a head search, a jump forward and a jump backward for the selected program. During a play operation, the server reads data of a specified program stored in a storage device and transmits the read data to the client terminal. Then, the client terminal displays the received data. However, once one of the stop, the head search, a jump forward and a jump backward command is executed, no data is transmitted from the server to the client terminal till the play command is executed.
The transmission rate of the transmission path between the server and each terminal is limited, i.e., the quantity of data transmitted for a certain period of time is limited. For this reason, in order to enable each client terminal to play a program whose data is stored in the server while having the program data transmitted from the server, video data of each program is stored in the server such that the bit rate (or the quantity of data reproduced or played per second) of video data of each program does not exceed the transmission rate of the transmission paths.
If the transmission paths between the server and the client terminals are considerably low as in case of ordinary telephone lines, it is necessary to reduce the frame rate, the resolution and/or the frame size, which degrades the picture quality of video objects.
It is an object of the invention to provide a video-on-demand system that enhances the quality of image by using the period of a play stoppage.